Safety Flash
IMCA Safety Flash 07/18 March 2018
These flashes summarise key safety matters and incidents, allowing wider dissemination of lessons learnt from them. The information below has been provided in good faith by members and should be reviewed individually by recipients, who will determine its relevance to their own operations. The effectiveness of the IMCA safety flash system depends on receiving reports from members in order to pass on information and avoid repeat incidents. Please consider adding the IMCA secretariat ([email protected]) to your internal distribution list for safety alerts and/or manually submitting information on specific incidents you consider may be relevant. All information will be anonymised or sanitised, as appropriate. A number of other organisations issue safety flashes and similar documents which may be of interest to IMCA members. Where these are particularly relevant, these may be summarised or highlighted here. Links to known relevant websites are provided at www.imca-int.com/links Additional links should be submitted to [email protected] Any actions, lessons learnt, recommendations and suggestions in IMCA safety flashes are generated by the submitting organisation. IMCA safety flashes provide, in good faith, safety information for the benefit of members and do not necessarily constitute IMCA guidance, nor represent the official view of the Association or its members.
1 Sustained Load Cracking in Aluminium Manufactured from Aluminium Alloys HE30/AA6082 and AA6351
A susceptibility to sustained load cracking (SLC) has been identified in cylinders manufactured from aluminium alloys of specific grades, manufactured between 1963 and 1995. Sustained load cracking is a metallurgical anomaly occurring in cylinders that have remained pressurised for sustained periods of time.
WorkSafe New Zealand Safety Alert
There have been two recent incidents of serious harm in the Asia-Pacific region caused by the catastrophic failure of self-contained underwater breathing apparatus (SCUBA) cylinders manufactured from aluminium alloy 6351. As a result of these incidents in August 2017 WorkSafe New Zealand issued a Safety Alert entitled “Cylinder design approvals withdrawn”. This Safety Alert may be accessed at: https://worksafe.govt.nz/about-us/news-and-media/cylinder-design-approvals-withdrawn/
In its Safety Alert WorkSafe New Zealand announced that it had decided to withdraw approval for SCUBA and self- contained breathing apparatus (SCBA) cylinder designs which used aluminium alloy 6351. The withdrawal came into effect from 31 October 2017.
UK Health and Safety Executive (HSE) Safety Bulletin
On 8 March 2018 the UK HSE issued Safety Bulletin ED 1-2018 entitled “Cylinders manufactured from aluminium alloys HE30/AA6082 and AA6351 and used primarily for gases for underwater breathing apparatus”.
The publication of this bulletin was prompted in part by the Asia-Pacific incidents, but also by an incident of serious harm caused by the failure of an HE30/AA6082 cylinder in England in 2017.
HSE Safety Bulletin ED 1-2018 may be accessed at: http://www.hse.gov.uk/safetybulletins/aluminium-cylinders.htm
The UK HSE bulletin states the following:
These cylinders should only be used if they have undergone thorough visual inspection and testing with an eddy- current device by a competent inspector (see inspection and testing requirements below).
Failure to conduct such inspection and testing could result in serious harm.
Cylinders to be inspected and tested include those used for SCUBA diving, those that supply breathing air through an umbilical hose and those used to fill SCUBA cylinders.
If you are unable to determine whether a particular cylinder is made from one of these alloys, remove it from service, safely release the gas and do not use it until the alloy can be identified and proper inspection and testing can be conducted. Cylinders that cannot be identified from markings on the cylinder must be removed from service, condemned and rendered incapable of holding pressure. Cylinders that fail visual inspection or eddy-current testing must be condemned and rendered incapable of holding pressure.
IMCA Guidance to Members
In view of the information provided by the Worksafe New Zealand alert and the UK HSE bulletin, IMCA recommends that cylinders manufactured from aluminium alloys HE30/AA6082 and AA6351 are not used on member worksites.
Members are advised to take the following actions: 1. Check if any cylinders are manufactured or suspected to be manufactured from aluminium alloys HE30/AA6082 or AA6351. 2. Check for specific alloy-related markings or for a date of manufacture (the earliest date stamped on the cylinder) prior to 1995. If there is reason to believe that a cylinder may be made from either of these alloys, then the cylinder should be removed from service. The gas should be safely released, the cylinder rendered incapable of holding pressure, and safely disposed of. 3. If it is not possible to determine the alloy and appropriate information, e.g. if the cylinder markings are missing or cannot easily be read, then the cylinder should be removed from service. The gas should be safely released, the cylinder rendered incapable of holding pressure, and safely disposed of.
Identification of Affected Cylinders
The WorkSafe New Zealand Safety Alert contains a list of cylinders affected by the withdrawal of WorkSafe cylinder design approvals. This has been reproduced overleaf as a means of assisting members to identify affected cylinders.
The UK HSE Safety Bulletin contains the following guidance on identifying cylinders manufactured from HE30/AA6082 and AA6351 aluminium alloys.
Cylinders stamped with any of the following markings are manufactured from HE30/AA6082 or AA6351: HE30 HOAL 1 HOAL 2 HOAL 3 HOAL 4 BS5045/3/B BS5045/3/B/S AA6351 P****X (as part of serial number) P****P (as part of serial number)
Note: On some small cylinders manufactured at Luxfer’s Aldridge, England, plant, the above markings may not be present. In that case, the alloy can be determined from the three-digit type number stamped around the base. If the three-digit number is of the form 1**, 3** or 5**, then the alloy of manufacture is AA6351.
List of Cylinders Affected by the Withdrawal of WorkSafe New Zealand Approval
2 Technical Service Bulletin from Broco/Rankin – BR22 Plus Exothermic Cutting Torch
The Association of Diving Contractors International (ADCI) has circulated an updated Technical Service Bulletin from Broco/Rankin relating to the BR22 Plus Exothermic Cutting Torch. This was sent out by Broco/Rankin on 13 March 2018.
The bulletin, available here, notes that “a recent report of an external oxygen leak from the control valve of a BR22 PLUS prompted an investigation to determine root cause. The result of that investigation concluded that machining debris in the O-ring groove of the Control Valve Nut has interfered with the Oxygen seal in the valve assembly”.
Members using this equipment should download and read the bulletin, and take the actions recommended therein.
Leak Test Procedure
This picture shows what a BR22 PLUS torch looks like Outfit the BR22 PLUS torch as shown with an 18” and the location of the valve stem leak. If this is not cutting rod inserted and the collet tightened what your torch looks like, do not continue!